>In the past this has created huge tidal waves/tsunamis that hit the east coast. It is active again.
>
>http://www.ibtimes.com/articles/230002/20111012/canary-islands-volcanic-eruption-el-hierro-evacuations.htm

Raise you one Icelandic volcano

http://www.guardian.co.uk/world/2011/oct/13/icelands-katla-volcano-eruption-imminent